Radiant heat superheater



Aug'. 22, 1933. C E, LUCKE 1,923,103

RADIANT HEAT SUPERHEATER Filed sept. 28. 1929 2 sheets-sheet 1 Fig j@ INENTOR Ma@ BY 4 WMM ATTORNEYS.

Aug. 22, 1933. c, E7 LucKE 1,923,103

-RADIANT HEAT SUPERHEATER Filed Sept. 28. 1929 2 Sheets-Sheet 2 F15/T46j Fig/T6.

"^ 72 J INVENTOR ATTORNEY Patented Aug. 22, 1933 f UNITED STATES PATENTOFFICE RADIANT HEAT SUPERHEATER Application September 28, 1929 SerialNo. 395,868

16 claims. (c1. 122-481) This invention relates to a novel and improvedradiant heat superheater, or the like, and the novel features will bebest understood from the following description and the 'accompanyingdrawings, in which I have shown selected embodiments of the invention,and in which- Fig. 1 is a vertical sectional view through the lowerportion of a furnace Wall and boiler showing one form of the invention;

Fig. 2 is a fragmentary view similar to Fig. 1,

but showing a different embodiment of the invention;

Fig. 3 is a View taken on the line 3-3 of Fig. 2;

Fig. 4 is a fragmentary rear view of some of the tubes appearing in Fig.3, but drawn on an enlarged scale.

Fig. 5 is a view on the line 5-5 of Fig. 4 and of Fig. 3;

Fig. 6 is a view on the line 6-6 of Fig. 4;

Figs. 7, 8 and 9 are views corresponding t0 Figs. 4, 5 and 6,respectively, but showing a different form of guiding means for thetubes;

Figs. 10, 11 and 12 are other views corresponding to Figs. 4, 5 and 6,but showing a third'form of guiding means.

Referring rst to Fig. 1, the invention is shown as embodied in asuperheater disposed in a furnace wall adjoining a combustion chamber 1disposed beneath a boiler, some of the tubes of which are indicated at2. It will be understood that the use of the invention is not restrictedto a boiler furnace, as the superheater may be installed as a separatelyred radiant heat superheater or the like. The tubes of the superheaterare indicated at 3 and their upper ends 4 are bent outwardly away fromthe furnace and extend outside the Wall where they enter holes in aheader 5. The outwardly bent nds are clamped between a stationary member6 and a removable member '7, suitable bolts 8 being used for thispurpose. This clamping means is better shown in Fig. 3. The lower ends 9of the tubes are also bent outwardly and joined to a header 10. Theseends 9 are similarly secured between a stationary clamping member 11 anda removable clamping member 12, by bolts 13. The headers 5 and 10 reston supporting blocks 15 which are secured to structural members 14.4Preferably, the clamps are tightened to such an extent as to preventtheir movement under expansion and contraction, and any movement beyondthe clamps is provided for by the blocks 15, upon which the headers mayslide.

In the form shown in Fig. 1, the tubes are pro vided. adjacent the ends4 and 9, with curved portions 16 joined by a reversed curve 17, so thattubes may freely expand and contract under the influence of the heat ofthe furnace to which they are subjected. Flexible insulating material 18may be provided on the backs or outer sides of the tubes.

In the form shown in Fig. 2, the parts are generally similar and similarreference characters apply to both. In this form, however, the tubes 3are formed in a curve extending inwardly toward the furnace so thatexpansion will take place in that direction rather than outwardly awayfrom the furnace, as in the form shown in Fig. 1. Both forms, however,will be seen to provide free and unrestrained expansion and contractionfor the tubes intermediate their ends, while the ends of the tubes areheld against movement in fixed supports independent of the headers. Theform shown in Fig. 2 however is considered preferable fory installationsin which high furnace temperatures are present. 'Ihe clamps areprotected by suitable refractory material19 against the action of theheat of the furnace.

Preferably, the ktubes are provided with means which will limit thetransverse displacement of one tube with respect to an adjacent tube,without interrupting the continuity of the wall formed by the tubeswhile, at the same time, permitting free flexing of the wall. This maybe achieved in different ways, some of which are illustrated in Figs. 4to 12, inclusive. In each case, the means employed is a guiding means,which allows a limited amount of displacement of one tube with respectto an adjacent tube.

Referring first to Figs. 4, 5 and 6, in which is shown the meansappearing in Fig. 3, this means comprises lugs 20 welded to the tubesand preferably at intervals along their lengths, a pair of lugs beingprovided on one tube to receive between them a lug on an adjacent tube.By this 9" arrangement, it will bc obvious that, while a tube may bowunder the influence of heat, nevertheless it will be maintained as partof a continuous wall formed by the tubes. At the same time, it will. beobvious that the tubes at different Darts of this wall may bowsubstantially different amounts without being restrained to anysubstantial degree in so doing.

In Figs. 7, 8 and 9, is shown another way in which the same result maybe obtained. In this form rearwardly extending lugs 21 are provided,these lugs being welded to the sides of adjacent tubes and beingprovided with vertically extending tongues 22 between which and thetubes are disposed clips 23. 110

In Figs. 10, 11 and 12, the same result is obtained by welding lugs 24to the tubes and by disposing between these lugs a T-shaped member 25,the head of which rests upon the top of the lugs 24, while its web 26 isreceived therebetween.. y

In all the forms shown it will be seen that substantially free expansionand contraction is possible at any point of the curved wall surfaceformed by the tubes. Ordinarily any condition in a furnace which'wouldaffect one tube would similarly affect adjoining tubes so that tubes atany point in the wall would act substantially the same. However, in thelength of a wall occupied by a superheater, or the like, conditions maybe varied considerably, but the conditions will vary more or lessgradually and it will be seen that the above constructions all permittubes in different parts of the wall to assume different positions withrespect to the normal position shown. In this way the curvature of thewall surface may change with temperature changes and unequal degrees ofcurvature are permitted from side to side of the wall withoutinterrupting its continuity. The arrangements therefor are veryflexible, permitting transverse movement of the tubes due to expansionand contraction and such change between adjacent tubes, both transverseand longitudinal, as may be necessary to meet local conditions in thefurnace.

I claim:-

1. In a furnace wall, a row of tubes subjected to the heat of thefurnace, having their opposite ends extending outwardly from thefurnace, headers connected to the tube ends, and means independent ofthe headers for holding the tubes in xed position at points adjacenttheir ends, the tubes intermediate said points being disposed on a flatcurve extending substantially from one of said points to the other andexposed to radiant heat from the furnace to permit expansion andcontraction thereof.

2. In a furnace wall, a row of tubes subjected to the heat of thefurnace, having their opposite ends extending outwardly from thefurnace, headers connected to the tube ends, means independent of theheaders for holding the tubes in fixed position at points adjacent theirends, the tubes intermediate said points being disposed on a flat curveextending substantially from one of said points to the other and exposedto radiant heat from the furnace to permit expansion` and contractionthereof, and means holding each tube in approximately constant relationto adjoining tubes.

3. In a furnace wall, a row of tubes subjected to the heat ofi thefurnace, having their opposite ends extending outwardly from thefurnace, headers connected to the tube ends, means independent of theheaders for holding the tubes in fixed position at points adjacent theirends, the tubes intermediate said points being disposed on a flat curveextending substantially from one of said points to the other and exposedto radiant heat from the furnace to permit expansion and contractionthereof, and means maintaining said tubes in position in the row.

4.` In a furnace wall, a row of tubes subjected to the heat of thefurnace, having their opposite ends extending outwardly from thefurnace, headers connected to the tube ends, means independent of theheaders for. holding the tubes in fixed position at points adjacenttheir ends, the tubes intermediate said points being disposed on a flatcurve extending substantially from one of said points to the other andexposed to radiant heat from the furnace to permit expansion andcontraction thereof, and refractory material disposed between saidholding means and the furnace.

5. In a furnace wall, a row of tubes subjected to the heat of thefurnace and having their opposite ends extending outwardly from thefurnace, headers connected to the tube ends, means supporting saidheaders, and clamps engaging opposite sides of said outwardly extendingends and holding them in fixed position, the tubes intermediate saidclamps being unsupported and curved to permit expansion and contractionthereof.

6. In a furnace wall, a row of tubes subjected to the heat of thefurnace and having their opposite ends extending outwardly from thefurnace, headers connected to the tube ends, means supporting saidheaders and ypermitting movement thereof due to expansion andcontraction of said tubes, and clamps engaging opposite sides of saidoutwardly extending ends and holding them in fixed position, the tubesintermediate said clamps being lunsupported and curved to permitexpansion and contraction thereof.

7. A radiantly heated steam superheater comprising, in combination witha furnace, a row of single loop steam conducting tubes constituting thestructural support of a curved furnace wall through which the furnacegases cannot pass, an outlet header connected to the outlet ends of thetubes and positioned externally of the furnace, and an inlet headerconnected to the inlet ends of the tubes and positioned externally ofthe furnace, the wall of tubes being bowed mainly in a single bendextending substantially from one end of the wall to the other so thatall intermediate portions of the wall are free to move laterally underthe influence of temperature changes.

8. A radiant superheater for steam power systems comprising, incombination with a furnace including a combustion chamber, an outsidewall of the combustion chamber, a. row of steam conducting superheatertubes forming the structural support of the wall, and superheater inletand outlet headers outside the combustion chamber and connectedrespectively to the inlet and outlet ends of the tubes, the tubes beingbowed inwardly of the furnace in a single bend or loop so as to preventdisruption of the wall by expansion and contraction, intermediateportions of the Wall being free to move in the direction of a normal tothe wall without disturbing the closures at the wall ends.

9. A furnace having a flexible external Wall section continuously bowedinwardly of the furnace and consisting of a layer of flexible heatinsulating material as a backing for a row of curved superheating tubesconveying steam to be radiantly heated.

10. A radiantly heated steam superheater comprising, in combination witha furnace, a row of loop steam conducting tubes constituting thestructural support of a furnace wall section through which the furnacegases cannot pass, an outlet header connected to the outlet ends of thetubes and positioned externally of the furnace, and an inlet headerconnected to the inlet ends of the tubesand positioned externally of thefurnace, the Wall of tubes being bowed so that all intermediate portionsof the wall are free to movelaterally under the influence of temperaturechanges.

11. An outside furnace wall, a supporting structure therefor, the saidsupporting structure consisting of a row of radiant heat absorbing tubesforming a steam superheating surface and having continuously curvedintermediate portion substantially free to expand and contract inwardlyof the furnace while maintaining the wall structure as a completefurnace wall, and means for fixedly supporting the tubes at their ends.

12. A radiant superheater for steam power system comprising, incombination with a furnace including a combustion chamber, an outsideWall section constituting a part of a wall of the combustion chamber, arow of steam conducting superheater tubes forming the structural supportof the section, heat resisting material adjacent the tubes, andsuperheater inlet and outlet headers outside the combustion chamber andconnected respectively to the inlet and outlet ends of the tubes, thetubes being bowed inwardly of the furnace in a bend or loop so as toprevent disruption of the section by expansion and contraction,intermediate portions of the section being free to move in the directionof a normal to the Wall without disturbing the closures at the Wallends.

13. A radiantly heated superheater comprising, in combination with afurnace, a row of looped fluid conducting tubes constituting thestructural support of a furnace wall section through which the furnacegases cannot pass, and an outlet chamber connected to the outlet ends ofthe tubes, the wall of tubes being bowed so that all intermediateportions of the wall are free to move laterally under the influence oftemperature changes.

14. In a furnace having enclosing walls, a radiant heat superheatercomprising a row of steam superheating tubes :arranged at the inner sideof one of said walls, each of said tubes having spaced end portions andan intermediate portion connecting said end portions and exposed to theradiant heat of said furnace, said end portions being xed in positionand said exposed intermediate portion being shaped in a continuousconvex curve extending inwardly of said furnace, whereby said curvedintermediate tube portions will tend to expand and contract in theirgeneral initial form under the influence of furnace temperature changes.

15. In a furnace having enclosing walls, a radiant heat superheatercomprising a row of steam superheating tubes lining the inner side ofone of said walls, each of said tubes having spaced end portions and anintermediate portion connecting said end portions and exposed to theradiant heat of said furnace, said end portions being fixed in positionand said exposed intermediate portion being shaped in a continuousconvex curve of a relatively large radius and extending inwardly of saidfurnace, whereby said curved intermediate tube portions will tend toexpand and contract in their general initial form under the influence offurnace temperature changes.

16. In a furnace having enclosing walls, a radiant heat superheatercomprising a row of closely spaced steam superheating tubes arranged atthe inner side of one of said walls, each of said tubes having spacedend portions and an intermediateportion connecting said end portions andexposed to the radiant heat of said furnace, means fixing said endportions in position, said exposed intermediate portion being shaped ina single continuous convex curve of a relatively large radius andextending inwardly of said furnace, whereby said curved intermediatetube portions will tend to expand and contract in theirgeneral initialform under the influence of furnace temperature changes, and meanslimiting relative movement of the intermediate portions of adjacenttubes.

' CHARLES E. LUCKE.

